Field
Communication systems may benefit from more accurate information regarding the passage of data through a network. For example, certain wireless communication systems may benefit from throughput guidance based on user plane insight and optional control plane and radio channel information.
Description of the Related Art
The majority of the content consumed via mobile devices, such as smartphones, tablets, and the like, originates from Over The Top (OTT) applications and services hosted and available on the Internet, in the clouds or distributed via content delivery networks (CDNs). The user experience of the OTT applications can depend on the efficiency of the data delivery through the mobile network, as well as the selection of the media attributes of the content to be downloaded. Media attributes can include, for example, the media/encoding rate.
The OTT content can be delivered through an interactive communication between the consumer and the server, for example a server of a content provider, whereas the network conditions can be indirectly inferred by the data transmission protocols. The inference can be based on empirical measurements executed at the server side. The empirical measurements can include, for example, round trip time (RTT), detection of data discards, and the like. The client may also send explicit receiver reports (RR) to the server to inform the server about dedicated client side measurements such as loss, delay, jitter, and the like.
Inferring the network status based on such measurements can make end-to-end content delivery suboptimal, as the server can only probe the network for the available resources and indirectly detect whether there are more resources available for the content server's data transmission or whether the network is already overloaded. Such lack of information may lead both to inefficient utilization of the available resources as well as to poor selection of the application level media attributes.
Good user experience of OTT multimedia applications, such as video downloads that generate the majority of the total mobile network traffic, can depend on two conditions: (1) the delivery rate of the content, such as video, web page, or the like, not exceeding the available bandwidth; and (2) efficient utilization of the available bandwidth during the whole content delivery session. The second condition may also be a prerequisite of efficient system operation.
These conditions can be important not only for optimal video delivery but also for any other OTT application. For example, when web page downloads exceeding the available bandwidth eventually trigger discards and retransmissions, the discards and retransmissions can increase the download time and cause user experience degradation.
The available bandwidth may continuously change during the lifetime of an application session or video download due to the fluctuations in the radio channel conditions, the mobility of the users, the activity on the concurrent data connections and the dynamic establishment and deactivation of bearers. Accordingly, the OTT servers can face a challenge of efficiently delivering content through a dynamic network environment about which they do not have enough insight. This inherently can lead to suboptimal performance.
While detailed network events are not known and should not, in the view of network operators, be known to the OTT servers, the OTT servers also have no knowledge of the available bandwidth, forcing the OTT servers to inefficiently probe for the available resources. The available bandwidth, however, would be sufficient information for the OTT servers to pace the content delivery optimally, for example to utilize the available bandwidth efficiently while at the same time not overloading the network.
Inefficient delivery can cause poor customer experience and/or user experience degradations as the time required to download the data is increased. For video downloads, this may even culminate in buffer depletion and stalling. Additionally, the lack of knowledge of the available bandwidth may also cause the improper selection of the content itself, such as starting to download a video with a media rate higher than the available bandwidth. In this case, no matter how optimally the available bandwidth is utilized, the user experience of the video application may still be poor, as downloading the content requires a throughput higher than the available bandwidth.
An additional potential problem with transmission control protocol (TCP) data transmission is that the TCP sender transmits data in bursts, for example a potentially large amount of data may be transferred at line speed, followed by idle periods when the sender waits for acknowledgements (ACKs) from the receiver. When the network buffers are not able to store the entire burst along the delivery path, tail drops may occur, which may cause poor performance, and may require the retransmission of significant amount of data and cause unfairness if multiple TCP connections share the same buffer. The line speed bursts may cause problems even if the overall TCP transmission rate, averaged over the bursts and idle periods, could be supported by the network.